Film deposition device and film deposition method

Abstract

To provide a film deposition device and a film deposition method capable of mitigating stress difference of a film deposited by magnetron sputtering.SOLUTION: A film deposition according to the present invention comprises a chamber, plural target mechanisms, and a drive control part. Each of the plural target mechanisms comprises a rotary target having a cylindrical target face around a central axis, and a magnet rotatable around the central axis and forming a magnetic field on the target face. The central axes are parallel to each other and parallel to a film deposition target face. The drive control part starts electric discharging for plasma production with the magnet directed to a center-oriented angle, and rotates the magnet from the center-oriented angle to an end-oriented angle during electric discharging, while a rotation angle when the magnet rotates to a side nearest the film deposition target face is an opposite angle, the rotation angle when the magnet is directed to a center side of the film deposition target face more than the opposite angle is the center-oriented angle, and the rotation angle when the magnet is directed to an end side of the film deposition target face more than the opposite angle is the end-oriented angle.SELECTED DRAWING: Figure 14

Description

[Technical field]

[0001] The present invention relates to a film formation apparatus and a film formation method by magnetron sputtering using a rotary target. [Background technology]

[0002] In sputtering, a sputtering gas is introduced into a vacuum and then turned into plasma by discharging the sputtering gas, and the ions generated collide with a target to generate sputter particles, which are then deposited on the object to be deposited. In magnetron sputtering, a magnet placed near the target is used to surround electrons in a magnetic field, creating a high-density plasma region near the target, and the ions are efficiently collided with the target, making it possible to speed up deposition (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-200520 A Summary of the Invention [Problem to be solved by the invention]

[0004] Here, in magnetron sputtering devices such as those described in Patent Document 1, the stress distribution of the deposited film becomes an issue. If deformation such as warping occurs in the object on which the film is deposited due to non-uniform stress distribution, there is a risk of interference with a post-process mask or post-process equipment, or misalignment during post-processing. For example, when manufacturing display panels, this can affect the reliability of the panel.

[0005] In view of the above circumstances, an object of the present invention is to provide a film formation apparatus and a film formation method capable of reducing the stress difference in a film formed by magnetron sputtering. [Means for solving the problem]

[0006] In order to achieve the above object, a film forming apparatus according to one aspect of the present invention includes a chamber, a plurality of target mechanisms, and a drive control unit. The multiple target mechanisms are each disposed within the chamber and include a rotary target having a cylindrical target surface around a central axis, and a magnet that is rotatable around the central axis and forms a magnetic field on the target surface, with the central axes being parallel to each other and parallel to the surface to be film-formed. The drive control unit determines the rotation angle when the magnet is rotated so that it is closest to the film-forming surface as the facing angle, the rotation angle at which the magnet faces toward the center of the film-forming surface relative to the facing angle as the central-facing angle, and the rotation angle at which the magnet faces toward the edge of the film-forming surface relative to the facing angle as the edge-facing angle, and starts discharging for plasma generation with the magnet at the central-facing angle, and rotates the magnet from the central-facing angle to the edge-facing angle during discharge.

[0007] Among the multiple target mechanisms, two target mechanisms closest to the center of the film formation target surface may be designated as a first target mechanism and a second target mechanism, the first target mechanism and the multiple target mechanisms further away from the center of the film formation target surface than the first target mechanism may be designated as a first target group, and the second target mechanism and the multiple target mechanisms further away from the center of the film formation target surface than the second target mechanism may be designated as a second target group.The drive control unit may rotate the magnets of the first target group at the same angle as each other and rotate the magnets of the second target group at the same angle as each other during discharge.

[0008] The drive control unit may, during discharge, make the rotation angle of the magnets of the first target group and the rotation angle of the magnets of the second target group symmetrical with respect to the center of the film formation target surface.

[0009] a center-facing angle of the magnets of the first target group is greater than 30° and is equal to or smaller than 60°, with the opposing angle being 0°; an end orientation angle of the magnets of the first target group is equal to or greater than −60° and smaller than −30°, with the opposing angle being 0°; the center-facing angle of the magnets of the second target group is equal to or greater than -60° and less than -30°, with the opposing angle being 0°; An end orientation angle of the magnets of the second target group may be greater than 30° and equal to or less than 60°, with the opposing angle being 0°.

[0010] The drive control unit may start a discharge for generating plasma with the magnet at the central orientation angle, rotate the magnet from the central orientation angle to the edge orientation angle during discharge, and end the discharge.

[0011] The drive control unit may start a discharge for generating plasma with the magnet at the central orientation angle, rotate the magnet from the central orientation angle to the edge orientation angle during the discharge, and further rotate the magnet from the edge orientation angle to the central orientation angle, and terminate the discharge.

[0012] Among the multiple target mechanisms, the two target mechanisms that are furthest from the center of the film formation target surface may be designated as the third target mechanism and the fourth target mechanism, respectively, with the third target mechanism being on the first target mechanism side and the fourth target mechanism being on the second target mechanism side. The first target group may include the target mechanism between the first target mechanism and the third target mechanism and the first target mechanism, and the second target group may include the target mechanism between the second target mechanism and the fourth target mechanism and the second target mechanism.

[0013] The drive control section may keep the rotation angles of the third target mechanism and the fourth target mechanism constant during discharge.

[0014] In order to achieve the above object, a film formation method according to one aspect of the present invention is a film formation method for performing sputtering film formation on a film formation target using a film formation apparatus including a chamber and a plurality of target mechanisms, each of which is disposed in the chamber and includes a rotary target having a cylindrical target surface around a central axis and a magnet that is rotatable around the central axis and forms a magnetic field on the target surface, the central axes of the target mechanisms being parallel to each other, the method comprising: The rotation angle when the magnet is rotated so that it is closest to the film-forming surface is defined as the facing angle, the rotation angle at which the magnet faces closer to the center of the film-forming surface than the facing angle is defined as the center-facing angle, and the rotation angle at which the magnet faces closer to the edge of the film-forming surface than the facing angle is defined as the edge-facing angle.Discharge for plasma generation is started with the magnet at the center-facing angle, and during discharge the magnet is rotated from the center-facing angle to the edge-facing angle. Effect of the Invention

[0015] As described above, according to the present invention, it is possible to provide a film formation apparatus and a film formation method capable of reducing the stress difference in a film formed by magnetron sputtering. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic diagram of a film forming apparatus according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram of the film forming apparatus. [Diagram 3] FIG. 2 is a perspective view of a target mechanism included in the film forming apparatus. [Figure 4] FIG. 2 is a cross-sectional view of the target mechanism. [Diagram 5] FIG. 1 is a schematic diagram showing the arrangement of magnets in the target mechanism. [Figure 6] 2 is a cross-sectional view of the vicinity of a floating shield of the film forming apparatus. FIG. [Figure 7] 5A and 5B are schematic diagrams showing a rotation angle of a magnet unit in the target mechanism. [Figure 8]5A and 5B are schematic diagrams showing a rotation angle of a magnet unit in the target mechanism. [Figure 9] FIG. 2 is a schematic diagram of the target mechanism and an object to be film-formed. [Figure 10] 6A to 6C are schematic diagrams showing a rotation operation of the target mechanism for the first target group. [Figure 11] 13A and 13B are schematic diagrams showing a rotation operation of the target mechanism for the second target group. [Figure 12] 3A to 3C are schematic diagrams illustrating a film forming method using the film forming apparatus. [Figure 13] 3A to 3C are schematic diagrams illustrating a film forming method using the film forming apparatus. [Figure 14] 3A to 3C are schematic diagrams illustrating a film forming method using the film forming apparatus. [Figure 15] 3A to 3C are schematic diagrams illustrating a film forming method using the film forming apparatus. [Figure 16] FIG. 2 is a schematic diagram showing a film forming method to be compared with the present invention. [Figure 17] FIG. 4 is a schematic diagram showing measurement positions of film stress according to an embodiment of the present invention. [Figure 18] FIG. 4 is a schematic diagram showing measurement positions of sheet resistance according to an embodiment of the present invention. [Figure 19] FIG. 2 is a schematic diagram of a Mo film according to an embodiment of the present invention. [Figure 20] FIG. 2 is a schematic diagram showing incident components of sputtered particles (Mo particles) according to an embodiment of the present invention. [Figure 21] 11 is a graph showing the ratio of incident components of Mo particles at the center of a substrate and at an end of a substrate in a film forming method according to a comparative example of the present invention. [Figure 22] 1 is a graph showing the ratio of incident components of Mo particles at the center of a substrate and at an end of a substrate in a film forming method according to an embodiment of the present invention. [Diagram 23] FIG. 13 is a schematic diagram showing measurement positions of film stress and incident component ratio according to a comparative example of the present invention. [Figure 24] 13 is a graph plotting the ratio of incident component D1 (incident angle 0-20°) and film stress according to a comparative example of the present invention. [Diagram 25]13 is a graph plotting the ratio of incident component D2 (incident angle 21-40°) and film stress according to a comparative example of the present invention. [Figure 26] 13 is a graph plotting the ratio of incident component D3 (incident angle 41-60°) and film stress according to a comparative example of the present invention. [Figure 27] 13 is a graph plotting the ratio of incident component D4 (incident angle 61-80°) and film stress according to a comparative example of the present invention. [Figure 28] 11 is a graph showing the ratio of incident components in the initial layer and total film thickness according to a comparative example of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0018] [About the deposition equipment] A film formation apparatus according to this embodiment will be described. Figures 1 and 2 are schematic diagrams of a film formation apparatus 100 according to this embodiment. As shown in Figures 1 and 2, the film formation apparatus 100 includes a vacuum chamber 101, a target mechanism 102, a floating shield 103, an end attachment plate 104, a rear attachment plate 105, a gas introduction unit 106, a substrate holder 107, and a drive control unit 108. A substrate 150, which is an object to be film-formed, is attached to the substrate holder 107, and a surface of the substrate 150 is a film-formation target surface 151.

[0019] Vacuum chamber 101 defines therein a sputtering space 111. A gas supply system 112 and an exhaust system 113 are connected to vacuum chamber 101. Gas supply system 112 is connected to gas inlet 106 and supplies sputtering gas to gas inlet 106. Exhaust system 113 is connected to a vacuum pump (not shown) and evacuates sputtering space 111 to a vacuum.

[0020] The target mechanism 102 is disposed in the sputtering space 111 and generates sputtered particles. FIG. 3 is a perspective view of the target mechanism 102, and FIG. 4 is a cross-sectional view of the target mechanism 102. As shown in FIG. 3, the target mechanism 102 extends along a central axis C (Z direction). As shown in FIG. 2, the film forming apparatus 100 has a plurality of target mechanisms 102. There is no particular limitation on the number of target mechanisms 102, as long as it is an even number. The central axes C of the plurality of target mechanisms 102 are all parallel to each other and are parallel to the film forming target surface 151 (see FIG. 2). The target mechanisms 102 are arranged along one direction (Y direction) perpendicular to the central axis C.

[0021] 4, the target mechanism 102 includes a backing tube 121, a rotary target 122, and a magnet unit 123. The backing tube 121 has a cylindrical shape centered on a central axis C. The backing tube 121 is connected to a sputtering power supply 131 (see FIG. 1) and functions as a cathode.

[0022] The rotary target 122 is layered on the outer circumferential surface of the backing tube 121, and is configured to be rotatable about a central axis C by a rotation mechanism (not shown). The rotary target 122 has a cylindrical target surface 122a around the central axis C. The rotary target 122 is made of a target material. The target material is, for example, Mo, but is not particularly limited to this.

[0023] The magnet unit 123 is disposed in the backing tube 121 as shown in Fig. 4, and is configured to be rotatable about the central axis C by a rotation mechanism (not shown). As shown in the figure, the magnet unit 123 includes a yoke 124 and a magnet 125. The magnet 125 extends along the central axis C and forms a magnetic field on the target surface 122a. Specifically, the magnet 125 includes an N-pole magnet 126 and an S-pole magnet 127, and the N-pole magnet 126 and the S-pole magnet 127 are disposed so as to face the rotary target 122 from inside the backing tube 121.

[0024] 5 is a schematic diagram showing the arrangement of magnets 125 in the target mechanism 102. As shown in the figure, the N-pole magnet 126 surrounds the S-pole magnet 127, and the N-pole magnet 126 and the S-pole magnet 127 extend along the central axis C (Z direction). Note that the magnetic poles of the N-pole magnet 126 and the S-pole magnet 127 may be opposite.

[0025] The floating shield 103 is disposed at both ends of each target mechanism 102 and has a floating potential. Fig. 6 is a cross-sectional view of the vicinity of the floating shield 103 of the film forming apparatus 100. As shown in the figure, the floating shield 103 has a cylindrical shape and is disposed around the backing tube 121 at the end of the target mechanism 102. The floating shield 103 is separated from the backing tube 121 and is insulated from the backing tube 121. Although Fig. 6 shows one end of the target mechanism 102, a similar floating shield 103 is provided at the opposite end.

[0026] 1, the end protection plate 104 is disposed between the end of the target mechanism 102 and the inner wall of the vacuum chamber 101, and prevents the adhesion of sputtered particles to the inner wall of the vacuum chamber 101. The end protection plate 104 is also connected to a sputtering power supply 131 and functions as an anode.

[0027] The rear adhesion shield 105 is disposed between the inner wall of the vacuum chamber 101 on the side opposite to the substrate 150 and the target mechanism 102, and prevents sputtering particles from adhering to the vacuum chamber 101. The rear adhesion shield 105 is also connected to a sputtering power supply 131 and functions as an anode.

[0028] Gas inlet 106 discharges sputtering gas supplied from gas supply system 112 (see FIG. 1) into sputtering space 111. This sputtering gas includes a sputtering gas and a reactive gas. The sputtering gas is a gas that is ionized by discharge, such as Ar. The reactive gas is a gas that undergoes a chemical reaction with particles of the target material resulting from the collision of the ions, such as O2. Gas inlet 106 may be provided on rear adhesion shield 105 as shown in FIG. 2, or may be provided at another position within sputtering space 111.

[0029] Substrate holder 107 is provided in sputtering space 111 and holds substrate 150. There are no particular limitations on the configuration of substrate holder 107 as long as it is capable of holding substrate 150. A floating mask that covers the peripheral portion of substrate 150 may be provided on the peripheral portion of substrate 150.

[0030] The drive control unit 108 includes a sputtering power supply 131 and a rotation drive source 132. The sputtering power supply 131 is a power supply for discharging power supplied to the target mechanism 102, and may be a DC (Direct Current) power supply or a high-frequency power supply such as an RF (Radio Frequency) power supply or a VHF (Very High Frequency) power supply. The rotation drive source 132 drives a rotation mechanism of the rotary target 122 and the magnet unit 123, and controls the rotation angle of the magnet unit 123.

[0031] The film forming apparatus 100 has the above-mentioned configuration. The film forming apparatus 100 may have other configurations instead of or in addition to the above-mentioned configurations.

[0032] [About rotation angle] The rotation angle of the magnet unit 123 will now be described. Figures 7 and 8 are schematic diagrams showing the rotation angle of the magnet unit 123. As shown in Figure 7, the rotation angle when the magnet 125 is rotated so that it is closest to the film formation target surface 151 is defined as the "opposition angle Af" and this rotation angle is defined as 0°. When a perpendicular line is drawn from the central axis C to the film formation target surface 151, the rotation angle at which this perpendicular line coincides with the center R of the magnet unit 123 corresponds to 0°.

[0033] 8, a rotation angle when the magnet unit 123 is rotated clockwise around the central axis C is defined as a positive rotation angle (+θ). Furthermore, as shown by a dashed line in FIG 8, a rotation angle when the magnet unit 123 is rotated counterclockwise around the central axis C is defined as a negative rotation angle (-θ).

[0034] 9 is a schematic diagram showing the target mechanisms 102 and the substrate 150 of the film formation apparatus 100. As shown in the figure, of the film formation target surface 151, the center in the arrangement direction (Y direction) of the target mechanisms 102 is referred to as a center 151c, and the ends in the same direction are referred to as ends 151e. Furthermore, of the target mechanisms 102, the two target mechanisms closest to the center 151c are referred to as a first target mechanism T1 and a second target mechanism T2, respectively.

[0035] Furthermore, of the target mechanisms 102, the two target mechanisms 102 that are furthest from the center 151c are designated as a third target mechanism T3 and a fourth target mechanism T4. Of these two target mechanisms 102, the third target mechanism T3 is the target mechanism 102 closer to the first target mechanism T1, and the fourth target mechanism T4 is the target mechanism 102 closer to the second target mechanism T2.

[0036] Further, the first target mechanism T1 and the target mechanism 102 between the first target mechanism T1 and the third target mechanism T3 are collectively defined as the first target group G1, and the second target mechanism T2 and the target mechanism 102 between the second target mechanism T2 and the fourth target mechanism T4 are collectively defined as the second target group G2. Therefore, when the number of target mechanisms 102 is eight, the first target group G1 and the second target group G2 each include three target mechanisms 102. When the number of target mechanisms 102 is ten, the first target group G1 and the second target group G2 each include four target mechanisms 102.

[0037] 10 is a schematic diagram showing the rotation angle of the first target group G1. As shown in the figure, the rotation angle at which the magnet 125 faces the center 151c side from the facing angle Af is defined as the center-facing angle Ac, and the rotation angle at which the magnet 125 faces the end 151e side from the facing angle Af is defined as the end-facing angle Ae. In the case of the first target group G1, the center-facing angle Ac is a positive rotation angle (+θ), and an angle greater than 30° and equal to or less than 60° is preferable. Moreover, the end-facing angle Ae is a negative rotation angle (-θ), and an angle greater than -60° and less than -30° is preferable.

[0038] It is preferable that the center-facing angle Ac and the end-facing angle Ae of each magnet unit 123 are the same among the first target group G1. For example, the center-facing angles Ac of the first target group G1 can all be 60°, and the end-facing angles Ae of the first target group G1 can all be -60°. Also, the center-facing angles Ac and the end-facing angles Ae can be different rotation angles among the first target group G1.

[0039] 11 is a schematic diagram showing the rotation angle of the target mechanism 102 included in the second target group G2. As in the first target group G1, in the second target group G2, the rotation angle at which the magnet 125 faces the center 151c side from the facing angle Af is defined as the center-facing angle Ac, and the rotation angle at which the magnet 125 faces the end 151e side from the facing angle Af is defined as the end-facing angle Ae. As shown in the figure, in the case of the second target group G2, the center-facing angle Ac is a negative rotation angle (-θ), and an angle of -60° or more and less than -30° is preferable. Moreover, the end-facing angle Ae is a positive rotation angle (+θ), and an angle of more than 30° and less than 60° is preferable.

[0040] It is preferable that the center-facing angle Ac and the end-facing angle Ae of each magnet unit 123 are the same among the second target groups G2. For example, the center-facing angles Ac of the second target group G2 can all be -60°, and the end-facing angles Ae of the second target group G2 can all be 60°. In addition, the center-facing angles Ac and the end-facing angles Ae of the second target groups G2 can be different rotation angles.

[0041] [Film formation method] A film formation method using the film formation apparatus 100 will be described below. The control of the rotation angle of the magnet unit 123 will be described later. FIG. 12 is a schematic diagram showing the film formation method using the film formation apparatus 100. In this film formation method, first, the sputtering space 111 is evacuated to a vacuum by the exhaust system 113 (see FIG. 1). After the sputtering space 111 is sufficiently depressurized, a sputtering gas is released from the gas inlet .

[0042] Next, while rotating the rotary target 122 provided in each target mechanism 102, the supply of discharge power to each target mechanism 102 is started. The sputtering gas is converted into plasma by this discharge power. This plasma is confined within the magnetic field generated by the magnet 125, forming a high-density plasma P as shown in FIG.

[0043] The ions forming the high-density plasma P collide with the target surface 122a, scattering sputtered particles, which are particles of the target material. The scattered sputtered particles react with the reactive gas and deposit on the film-forming target surface 151 to form a film. The supply of discharge power is continued in this state until the film thickness reaches the desired thickness.

[0044] [Controlling the rotation angle] The rotation angle of the magnet unit 123 during film formation will be described. Fig. 13 and Fig. 14 are schematic diagrams showing the rotation angle of the magnet unit 123 during film formation. In the film formation apparatus 100, as shown in Fig. 13, the magnet unit 123 of each target mechanism 102 is set at a central orientation angle Ac (see Figs. 10 and 11) to start discharge for plasma generation and generate high-density plasma P. As described above, the first target group G1 has a central orientation angle Ac that is a positive rotation angle (+θ), and the second target group G2 has a central orientation angle Ac that is a negative rotation angle (-θ).

[0045] After the discharge starts, the magnet unit 123 of each target mechanism 102 is rotated from a center-facing angle Ac to an end-facing angle Ae (see FIGS. 10 and 11) as shown by the arrows in Fig. 14. The high-density plasma P rotates following the rotation of the magnet unit 123, and magnetron sputtering progresses. The rotation angle of the magnet unit 123 of the third target mechanism T3 and the fourth target mechanism T4 is kept constant during the discharge.

[0046] It is preferable to set the center-facing angles Ac, end-facing angles Ae, and rotation speeds to be the same among the first target group G1, i.e., to synchronize the rotation of each magnet unit 123. In this case, for example, the center-facing angles Ac of the first target group G1 can all be 60°, the end-facing angles Ae can all be -60°, and the rotation angles can all be 10 rpm.

[0047] Similarly, it is preferable to set the center-facing angles Ac, end-facing angles Ae, and rotational speeds to the same among the second target group G2, i.e., to synchronize the rotation of each magnet unit 123. In this case, for example, the center-facing angles Ac of the second target group G2 can all be -60°, the end-facing angles Ae can all be 60°, and the rotation angles can all be 10 rpm.

[0048] Furthermore, by setting the center-facing angle Ac of the first target group G1 and the end-facing angle Ae of the second target group G2 to the same angle (e.g., 60°), and the end-facing angle Ae of the first target group G1 and the center-facing angle Ac of the second target group G2 to the same angle (e.g., -60°), and matching the rotational speeds, the rotational angles of the magnet unit 123 between the first target group G1 and the second target group G2 can be made symmetrical with respect to the center 151c.

[0049] 15 is a schematic diagram showing the movement of the magnet unit 123 during discharge, and shows the target mechanism 102 for the first target group G1. In magnetron sputtering using the film formation apparatus 100, film formation can be performed by two types of methods, one pass and two passes.

[0050] In one pass, as shown in Fig. 15(a), discharge is started with the magnet unit 123 at the center orientation angle Ac, and then the magnet unit 123 is rotated toward the end orientation angle Ae to set the facing angle Af as shown in Fig. 15(b). The magnet unit 123 is further rotated toward the end orientation angle Ae to set the end orientation angle Ae as shown in Fig. 15(c). In this way, when the magnet unit 123 reaches the end orientation angle Ae, the discharge is terminated.

[0051] In the second pass, the magnet unit 123 is rotated to the end-facing angle Ae (FIG. 15(c)) in the same manner as in the first pass, and then rotated toward the center-facing angle Ac to set the opposing angle Af as shown in FIG. 15(d). Furthermore, the magnet unit 123 is rotated toward the center-facing angle Ac to set the center-facing angle Ac as shown in FIG. 15(e). When the magnet unit 123 reaches the center-facing angle Ac, the discharge is terminated.

[0052] Figure 15 shows the target mechanism 102 for the first target group G1, but the target mechanism 102 for the second target group G2 similarly rotates from the center-facing angle Ac to the edge-facing angle Ae in one pass, and rotates back and forth from the center-facing angle Ac to the center-facing angle Ac in two passes.

[0053] The rotation angle of the magnet unit 123 of the third target mechanism T3 and the fourth target mechanism T4 is constant during discharge. The rotation angle of the magnet unit of the third target mechanism T3 can be, for example, 5°, and the rotation angle of the magnet unit of the fourth target mechanism T4 can be, for example, -5°. The magnet units 123 of the third target mechanism T3 and the third target mechanism T4 may be rotated during discharge. In this case, the third target mechanism T3 may be rotated in the same manner as the first target group G1, and the fourth target mechanism T4 may be rotated in the same manner as the second target group G2. The third target mechanism T3 may be rotated independently of the first target group G1, and the fourth target mechanism T4 may be rotated independently of the second target group G2.

[0054] The above is how the film is formed by the film forming apparatus 100. The above-described film forming process may be performed by a user using the film forming apparatus 100, or may be performed by the drive control unit 108 controlling the sputtering power supply 131 and the rotation drive source 132.

[0055] [Effects of deposition equipment] The effects of the film formation apparatus 100 will be described. As described above, in the film formation apparatus 100, magnetron sputtering is performed while rotating the magnet units 123 of the first target group G1 and the second target group G2 between the center-facing angle Ac and the end-facing angle Ae. This makes it possible to reduce the difference in stress of the film formed on the film formation target surface 151 (hereinafter, film stress) and to reduce the difference in sheet resistance (Rs) (see Examples).

[0056] The reason for this is that the film stress of a film formed by magnetron sputtering depends on the ratio of components that are obliquely incident on the film-forming surface 151 in the early stages of film formation (see the Examples). The film stress of a film formed by magnetron sputtering is generally tensile stress at the center of the film and compressive stress at the outer periphery of the film. In the film formation method of the present invention, the component of sputtered particles that are incident obliquely on the center of the film-forming surface 151 is relatively reduced. As a result, the tensile stress at the center of the film is reduced, and the difference with the compressive stress at the outer periphery of the film is reduced. Therefore, the film formation method of the present invention is capable of reducing the film stress difference.

[0057] The range of the center-facing angle Ac and the edge-facing angle Ae is preferably greater than 30° and less than ±60°. Specifically, it is preferable that the center-facing angle Ac of the first target group G1 is greater than 30° and less than 60°, and the edge-facing angle Ae is -60° or greater and less than -30°, and that the center-facing angle Ac of the second target group G1 is -60° or greater and less than -30°, and the edge-facing angle Ae is greater than 30° and less than 60°. By setting the center-facing angle Ac and the edge-facing angle Ae in this range, it is possible to further reduce the film stress difference and the sheet resistance difference (see Examples).

[0058] The rotational operation of the magnet unit 123 during film formation may be either one pass or two passes. In the case of one pass, it is possible to further reduce the film stress difference on the film formation target surface 151. On the other hand, in the case of two passes, it is possible to further reduce the sheet resistance difference on the film formation target surface 151 (see the examples). Therefore, either one pass or two passes can be selected depending on whether the film stress difference or the sheet resistance difference on the film formation target surface 151 is more important.

[0059] [Comparison of deposition methods] FIG. 16 is a schematic diagram showing a film formation method using a film formation apparatus 300 that is used as a comparison target in the following examples. The film formation apparatus 300 has the same configuration as the film formation apparatus 100 except for the rotational operation of the magnet units, so the same reference numerals as the film formation apparatus 100 will be used for the explanation. As shown in the figure, in the film formation apparatus 300, the target mechanisms 102 other than the target mechanisms 102 at both ends are set as a target group G3. In the target group G3, all the magnet units 123 rotate synchronously between a rightward angle Ar and a leftward angle Al. The rightward angle Ar is a positive rotation angle (+θ) and is 30° or 60°. The leftward angle Al is a negative rotation angle (-θ) and is -60° or -30°.

[0060] In the film formation apparatus 300, the magnet units 123 of the target group G3 are set to a rightward angle Ar at the start of film formation, and after discharge begins, each magnet unit 123 is rotated toward a leftward angle Al. In the case of one pass, discharge ends when each magnet unit 123 reaches the leftward angle Al. In the case of two passes, discharge ends when each magnet unit 123 again reaches the rightward angle Ar. The rotation angles of the magnet units 123 of the third target mechanism T3 and the fourth target mechanism T4 are kept constant during discharge, with the rotation angle of the magnet unit 123 of the third target mechanism T3 being 5° and the rotation angle of the magnet unit 123 of the fourth target mechanism T4 being -5°.

[0061] [Embodiments of the present invention] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made. At least two of the characteristic parts described in the above embodiment can be arbitrarily combined. EXAMPLES

[0062] [Evaluation of film quality by rotational motion] A Mo film (thickness 300 nm) was formed on a glass substrate by the film formation method according to the embodiment and the comparative example of the present invention, and the film stress difference and the uniformity of the sheet resistance (Rs) of the Mo film were measured. The following [Table 1] shows the film formation method and the measurement results.

[0063] [Table 1]

[0064] In Table 1, "rotational operation" refers to the rotational operation during discharge of the magnet units provided in each target mechanism. Rotational operation "A" is a rotational operation that rotates the magnet units of the target mechanisms, except for the target mechanisms at both ends, between a rightward angle Ar and a leftward angle Al, as shown in Fig. 16. Rotational operation "B" is a rotational operation that rotates the first target group and the second target group between a center-facing angle Ac and an end-facing angle Ae, as shown in Fig. 13. Therefore, samples 3, 5, and 6 correspond to examples of the present invention, and samples 1, 2, and 4 correspond to comparative examples of the present invention.

[0065] In Table 1, "Rotation Angle" refers to the rotation angle of the center angle Ac and the end angle Ae in rotation operation "B", for example, "±60°" means that the center angle Ac is 60° and the end angle Ae is -60° or the center angle Ac is -60° and the end angle Ae is 60°. In rotation operation "A", it refers to the rotation angle of the right angle Ar and the left angle Al, and means that the right angle Ar is 60° and the left angle Al is -60°.

[0066] In Table 1, "Number of passes" indicates whether the film was formed in one pass or two passes (see Figure 15). In Table 1, "Film stress difference" is the film stress difference of the formed Mo film. Figure 17 shows the measurement points (encircled by dashed lines in the figure) of the film stress of a Mo film ("M" in the figure) formed on a glass substrate. In the Mo film, the film stress at the center ("A" in the figure) is tensile stress, and the film stress at the outer periphery ("B" to "I" in the figure) is compressive stress. The film stress difference is the maximum value of the difference between the tensile stress at the center and the compressive stress at the outer periphery. A small film stress difference is preferable as it prevents deformation of the glass substrate.

[0067] In Table 1, "Rs uniformity" is the uniformity of Rs (sheet resistance) of the deposited Mo film. Figure 18 shows the measurement points (enclosed by dashed lines in the figure) for sheet resistance in the Mo film ("M" in the figure), and the uniformity of the sheet resistance value at each measurement point is defined as "Rs uniformity." A small Rs uniformity value is preferable because it indicates uniform quality of the Mo film.

[0068] Comparing sample 1 and 3 for rotational motion, it can be seen that sample 3 (rotational motion "B") has a 207 MPa lower film stress difference and a 0.3% lower Rs uniformity than sample 1 (rotational motion "A"). Therefore, rotational motion "B" is preferable.

[0069] Comparing the rotation angles of Samples 2 and 4, it can be seen that Sample 4 (rotation angle ±60°) has a 433 MPa lower film stress difference and a 0.2% lower Rs uniformity than Sample 2 (rotation angle ±30°). Therefore, a rotation angle of ±60° is preferable.

[0070] Comparing Samples 1 and 2 with regard to the "number of passes," it can be seen that Sample 2 (2 passes) has a 140 MPa increase in membrane stress difference and a 0.6% decrease in Rs uniformity compared to Sample 1 (1 pass). Therefore, when placing importance on membrane stress difference, 2 passes are preferable, and when placing importance on Rs uniformity, 1 pass is preferable.

[0071] From the above, by performing rotation operation "B", i.e., rotating the first target group and the second target group between the center-facing angle Ac and the end-facing angle Ae, it is possible to alleviate the film stress difference of the Mo film and improve the Rs uniformity. Furthermore, by setting the rotation angle of the magnet unit to ±60°, the film stress difference can be further alleviated and the Rs uniformity can be further improved. Also, it is possible to select whether the film stress difference or the Rs uniformity is to be improved by changing the number of passes.

[0072] [Difference in incident components due to rotational movement] A Mo film (thickness 300 nm) was formed on a glass substrate by the film formation method according to the embodiment and the comparative example of the present invention, and the incident component was measured. Figure 19 is a schematic diagram of a Mo film, showing a Mo film ("M" in the figure) formed on a glass substrate ("G" in the figure). 50% of the Mo film on the glass substrate G side is called the "initial layer", and the other 50% is called the "surface layer".

[0073] 20 is a schematic diagram showing incident components of Mo particles (sputtered particles) incident on a glass substrate G. In the figure, the component with an incident angle of 0-20° with respect to the surface of the glass substrate G is incident component D1, the component with an incident angle of 21-40° is incident component D2, the component with an incident angle of 41-60° is incident component D3, and the component with an incident angle of 61-80° is incident component D4.

[0074] Figure 21 is a graph showing the incident component ratios of Mo particles at the center and edge of the glass substrate (690 mm from the center of the substrate) by the above-mentioned rotation operation "A" (1 pass), and shows the incident component ratios of the initial layer in Figure 19. As shown in the figure, there is a large difference in the component ratio (D4) of oblique incidence (incident angle 61-80°) between the center of the substrate and the edge of the substrate, which is thought to result in a large difference in film stress.

[0075] Figure 22 is a graph showing the incident component ratios of Mo particles at the center and edge of the glass substrate (690 mm from the center of the substrate) by the above-mentioned rotation operation "B" (1 pass), and shows the incident component ratios of the initial layer in Figure 19. As shown in the figure, the difference in the component ratio (D4) of oblique incidence (incident angle 61-80°) is small between the center of the substrate and the edge of the substrate, which is thought to result in a small film stress difference.

[0076] In addition, a Mo film (thickness 300 nm) was formed on a glass substrate by the film formation method according to the comparative example, and the film stress and the incident component ratio were measured for each position of the Mo film. Figure 23 is a schematic diagram showing the measurement positions on the Mo film ("M" in the figure). The following [Table 2] is a table showing the film stress and the incident component ratio at each position shown in Figure 23.

[0077] [Table 2]

[0078] Fig. 24 is a graph plotting the ratio of incident component D1 (incident angle 0-20°) in [Table 2] versus film stress, Fig. 25 is a graph plotting the ratio of incident component D2 (incident angle 21-40°) in [Table 2] versus film stress, Fig. 26 is a graph plotting the ratio of incident component D3 (incident angle 41-60°) in [Table 2] versus film stress, and Fig. 27 is a graph plotting the ratio of incident component D4 (incident angle 61-80°) in [Table 2] versus film stress.

[0079] As shown in Fig. 24, the correlation coefficient between the ratio of incident component D1 (incident angle 0-20°) and film stress was -0.54, which was small, and the correlation between them was low. Also, as shown in Fig. 25, the correlation coefficient between the ratio of incident component D2 (incident angle 21-40°) and film stress was -0.41, which was small, and the correlation between them was low. Furthermore, as shown in Fig. 26, the correlation coefficient between the ratio of incident component D3 (incident angle 41-60°) and film stress was 0.18, which was small, and the correlation between them was low.

[0080] On the other hand, as shown in Fig. 27, the correlation coefficient between the ratio of the incident component D4 (incident angle 61-80°) and the film stress was as large as 0.96, and the correlation between them was high. Therefore, it can be said that the film stress of the Mo film is dependent on the incident component D4, and that control of the incident component D4 is important for the film stress.

[0081] Furthermore, a Mo film (thickness 300 nm) was formed on a glass substrate by the film formation method according to the comparative example, and the incident component ratio in the initial layer and total film thickness (see FIG. 19) was measured for each Mo film sample. FIG. 28 is a graph showing the measurement results. As shown in the figure, the incident component ratio in the total film thickness was equivalent among samples 1 to 3, but the film stress was different. On the other hand, the incident component ratio in the initial layer was different among samples 1 to 3. As described above, since the correlation coefficient between the ratio of incident component D4 (incident angle 61-80°) and the film stress is large, it can be said that the film stress can be adjusted by controlling the ratio of incident component D4 in the initial layer. [Explanation of symbols]

[0082] 100...Film deposition equipment 101...Vacuum chamber 102...Target mechanism 103…Floating Shield 104...End adhesion prevention plate 105...Back attachment prevention plate 106…Gas inlet 107...Substrate holder 108...Drive control unit 121…Backing tube 122...Rotary target 123...Magnet unit 124…York 125…Magnet 131...Sputter power supply 132...Rotational drive source

Claims

1. A chamber; a plurality of target mechanisms, each of which is disposed within the chamber, the target mechanisms including a rotary target having a cylindrical target surface around a central axis, and a magnet that is rotatable around the central axis and forms a magnetic field on the target surface, the central axes of the target mechanisms being parallel to each other and to a film-forming target surface; a drive control unit which starts a discharge for generating plasma with the magnet at the central orientation angle and rotates the magnet from the central orientation angle to the edge orientation angle during discharge, the drive control unit defining a rotation angle when the magnet is rotated so that it is closest to the film formation target surface as an opposing angle, a rotation angle at which the magnet faces closer to the center of the film formation target surface than the opposing angle as a central orientation angle, and a rotation angle at which the magnet faces closer to the edge of the film formation target surface than the opposing angle as an edge orientation angle; A film forming apparatus comprising:

2. The film forming apparatus according to claim 1 , Among the plurality of target mechanisms, two target mechanisms closest to the center of the film formation target surface are defined as a first target mechanism and a second target mechanism, respectively, the first target mechanism and a plurality of target mechanisms spaced apart from the center of the film formation target surface from the first target mechanism are defined as a first target group, and the second target mechanism and a plurality of target mechanisms spaced apart from the center of the film formation target surface from the second target mechanism are defined as a second target group. During discharge, the drive control unit rotates the magnets of the first target group at the same rotation angle as each other, and rotates the magnets of the second target group at the same rotation angle as each other. Film deposition equipment.

3. The film forming apparatus according to claim 2, The drive control unit controls the rotation angle of the magnets of the first target group and the rotation angle of the magnets of the second target group to be symmetrical with respect to the center of the film-forming target surface during discharge. Film deposition equipment.

4. The film forming apparatus according to claim 3, a center orientation angle of the magnets of the first target group is greater than 30° and is equal to or smaller than 60°, with the opposing angle being 0°; an end orientation angle of the magnets of the first target group is equal to or greater than −60° and less than −30°, with the opposing angle being 0°; the central orientation angle of the magnets of the second target group is −60° or more and less than −30° with the opposing angle being 0°, The end orientation angle of the magnets of the second target group is greater than 30° and is equal to or smaller than 60°, with the opposing angle being 0°. Film deposition equipment.

5. The film forming apparatus according to claim 1 , The drive control unit starts a discharge for generating plasma with the magnet at the central orientation angle, rotates the magnet from the central orientation angle to the edge orientation angle during the discharge, and ends the discharge. Film deposition equipment.

6. The film forming apparatus according to claim 1 , The drive control unit starts a discharge for generating plasma with the magnet at the central orientation angle, rotates the magnet from the central orientation angle to the edge orientation angle during the discharge, and further rotates the magnet from the edge orientation angle to the central orientation angle, and ends the discharge. Film deposition equipment.

7. The film forming apparatus according to claim 2, Among the plurality of target mechanisms, two target mechanisms furthest from the center of the film formation target surface are designated as a third target mechanism and a fourth target mechanism, respectively, and the third target mechanism is on the first target mechanism side and the fourth target mechanism is on the second target mechanism side. The first target group includes the target mechanism between the first target mechanism and the third target mechanism and the first target mechanism, and the second target group includes the target mechanism between the second target mechanism and the fourth target mechanism and the second target mechanism. Film deposition equipment.

8. The film forming apparatus according to claim 7, The drive control unit keeps the rotation angles of the third target mechanism and the fourth target mechanism constant during discharge. Film deposition equipment.

9. A film formation method for performing sputtering film formation on a film formation target using a film formation apparatus including a chamber and a plurality of target mechanisms, each of which is disposed in the chamber and includes a rotary target having a cylindrical target surface around a central axis and a magnet that is rotatable around the central axis and forms a magnetic field on the target surface, the central axes of the target mechanisms being parallel to each other, the method comprising: The rotation angle when the magnet is rotated so that it is closest to the film formation target surface is defined as the facing angle, the rotation angle at which the magnet faces closer to the center of the film formation target surface than the facing angle is defined as the center-facing angle, and the rotation angle at which the magnet faces closer to the edge of the film formation target surface than the facing angle is defined as the edge-facing angle. Discharge for plasma generation is started with the magnet at the center-facing angle, and during discharge, the magnet is rotated from the center-facing angle to the edge-facing angle. Film formation method.

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